GLOBAL WARMING DAYS & TIMING THE BEAUTIFUL FLOWER
Obviously the time a cultivar takes for a tiny shoot to produce a good stem and a full flower varies from cultivar to cultivar. The showmen get to know the dahlias they use, and can tell within a few days how long that period will be, but with new and as yet untried seedlings it becomes slightly harder. Most of the top growers hold all this valuable information in their heads, so add to this fact the number of plants of each variety they handle, and is it any wonder they will have sufficient flowers to select a winning vase or three on show day. In my case all I want to do is have the new flowers ready for the seedling classes at the NDS show at Shepton Mallet unlike last year. Another favourite place to show them off is at Wisley when the RHS and NDS joint committee meet as this is about the furthest I can go without friendly assistance. Of course should I have flowers ready when a show is being held fairly near Iíll be there providing there are seedling classes. A very rough estimate for bloom development would be eight weeks from when the plant is either stopped or cut back, but of course the bigger the flower the longer it takes. Cutting back has been given the nickname ďKnock backĒ a pretty good description as some times the early plant is hacked down to within several inches of the ground. As Dave Spencer told me when I approached him about the subject, ďYouíve got to be brave because you are relying on the root system the plant has made up to that point to produce the stems of the next set of flowersĒ I was a bit apprehensive when I ran Dave because guys such as he must get thoroughly sick and tired of continual phone calls, but far from it, he explained the act of `Knock Backí exquisitely ,and I gained a very important piece of advice for the cost of a phone call. I should imagine attending a lecture by this man would be worth its weight in gold. Of course it will mean experimenting regards the actual date the deed is done, but letís say if I donít succeed on the first occasion Iíll adjust my times and try again the following year. Like us humans, every variety has its particular trait, so beware, and expect surprises. Another thing that affects timing is of course the weather; the summer of 2006 bore this out with flowers opening far too quickly to the detriment of the finished bloom. So while the bud or bloom is developing, and the weather is over cast it will slow the flowers development down, this is obvious. A great email friend of mine in Australia called John Menzel has studied this to such a degree he could tell you within ten minutes when a particular bloom could be at its peak showing stage because he knows his subject and the area he lives in. He uses varying degrees of shading when the blooms are opening, but then this is Australia, and of course with their continual sunshine if this wasnít done he would have no blooms at all.
The next important moment in the development of a dahlia plant is, at what stage do you secure the bud? Dis-budding and securing the bud is the last stage that can influence the time each flower takes to open, get this wrong at your peril, it makes the difference of having flowers for that particulate date or not, itís as simple as that. I have in the past run on stems to the next bud, but never found it to be satisfactory; most times the resultant blooms are light of petal perhaps I donít feed enough? In case you donít already know about dis-budding let me explain, you have a cluster of buds at the end of the stem, and each will if left to nature open at specific times. If you take the centre bud, this will open earlier than the side bud by about a week, this bud is often called a wing bud, so it is obvious that buds lower down will open progressively later, the further down the stem you go the later the bloom will be. Of course if you go right down, you are approaching the ďKnock backĒ situation again, but at this stage in the year it would be too late for all but the very last shows. I am not a showman, not in the strictest sense of the word, I like showing off, but thatís a different matter. So for anyone in a similar position to me, here are a few dates I have worked out. I havenít got any particular theory it is just a rough guide for each group.
The hardest to my mind to judge are the giants; well you only get one crack at them, bit like an early flowering chrysanthemum. So if you miss the date youíve got another twelve months to wait. As I have only raised one reasonable giant called Argyle Gold Top, and I donít consider it good enough to beat the very best at this stage I donít have to worry because the only place Argyle Gold Top will be growing will be on Bob Hendleyís dahlia field at Sturminster Newton. However for the benefit of anyone who didnít read the excellent article written by Wayne Holland a year or two back called ďChasing the BudĒ here are the bones of the article. Instead of taking the buds nearest the central bud the whole process is started a little earlier and the shoots lower down are removed at a very minute stage. This induces the sap to fill out the up portion of the plant, and in turn produce a heavier stem to support a larger flower. In other words you start from the other end. Of course the side buds next to the main bud should not be left to long or the concept is wasted. I should think it works on giantís best, but it could be used on any group I suppose. Now let me give you my rough guide for securing the buds of all groups, and the number of days it takes from securing the bud to the show date, then there will be every chance youíll be able to put up a vase or two, and more vases mean a better show, but remember the location you live in is the biggest factor of all which includes the aspect of the ground.. For you experts and I know we have a few in our midst, go and make a cup of tea.
Starting with the giantís they can take up to 50 days. Large would be nearer 40 days. Medium could take say 30 days. Smalls down to 25 days and miniatureís 20 days. I havenít worked out the timing of the Colleretteís yet, but they open so fast that like the good olí London buses if you miss one another comes along very quickly. Now count back the days from the show you wish to exhibit a particular group in, and secure your buds around the date it falls on, remembering to have some buds a few days either way. Now thatís about all you can do regards the timing of your plants, but there are other things you can do to delay them when the buds are taken. Nothing now will make them sooner than their time clock will allow, except of course if the weather turns warm and sunny, but we donít want it to be to hot when the flowers are opening, or they will open to quickly loosing quite a bit of colour, and substance. So in order to protect the colour especially the darker ones and delay flowering a little why not use a shade cloth. You can build an impressive compound like John Menzel, or be like me and opt for a simple over head affair made up of bamboo canes. Of course it has to be strong and secure enough to take a battering, but being light and strong it will have an advantage, remember a Willow can bend. Fortunately I donít live in an exposed area out in the `Bushí like John Menzel does at Winkie.
A 30% shade cloth will not only delay flowering and protect the colour, but it will also put a few more inches on the height of the plants, and as many of you grow in town like me you know that your plants are already over a foot or more higher than they would have been in a field position. So remember this, and try to arrange that on dull days this shade cloth can be drawn back like the lounge curtains. The only difference is these nets will be at a forty five degree angle and some distances from the plants so the shade is thrown on to the blooms without actually being over them, the operation is also meant to divert the winds power over and away from the developing blooms as well as giving them the shade they need, least thatís the theory. Of course I could have made covers similar to the ones I had when I exhibited early flowering chrysanthemums, but as the dahlia flower is well able to stand any amount of rain it seems pointless to cover them completely as the only place theyíll be shown is in a seedling class or at Wisley when the Executive Committee meet, but of course when this season is over I may well change my tune.
Iím purposely missing out anything to do with feeding, sufficed to say if you have your soil well nourished, and have built up a reasonable fertile environment a good base dressing and a few weak liquid feeds will hone them to show potential. If however your ground isnít in good heart a few more liquid feeds wonít go a miss. Learn to, as John Menzel often says `Read Your Plantsí because when you see a good vase of flowers you will almost certainly see a good vase of leaves, most of this comes from experience, and of course the more intelligent you are the quicker you pick it up, must be why itís taken me so long to get it right, but no matter what species you grow the leaves on it will tell you all.
Question, what influences the growth of a plant more than any thing else, and Iíll give you a clue ďLast year we didnít have muchĒ correct rain. Itís hardly surprising that this would affect growth considering the dahlia plant is made up of about 80% water, some say more. Iíd have questioned this a few years back, but after not being too good after getting the tubers up a year or so ago the mountain of old discarded tops had to be left where they were for some considerable time. Consequently when I felt like getting shot of them they had diminished to a manageable heap. Of course when we water there are different methods used, the hand held hose in the right hands is okay. I know Iíve been doing it this way for many years, and although itís time consuming you can give the plant the right amount, but since the John Menzel article I wrote describing a typical Australian dahlia season in his region Iím sure the method I use, and most likely the way you do it can be done not only more efficiently, but in a way that benefits the plants we grow. Add to this the savings on our valuable water supply, and it becomes the right thing to do. The things mankind does of course has an affect on our climate, but I donít think it is quite as much as some are trying to make out, none the less anything we can do to help the world to clean up the mess we make must be a plus. So Iíll leave it to those in charge to find out what we should be doing, and the boffins to write about it and get pulled over the coals for.
Okay you ask, come on clever clogs whatís this revolutionary way of watering? Well like the blood goes round your body, so the water needs to circulate around and into our plants. The word is `Pulseí the tubing used is called a `Drip Lineí which has built in valves at roughly twelve inch intervals along its entire length. These valves can become blocked when used for supplying the plants with anything other than water, or if sandy particles run through the system. The remarkable thing is they unblock their selves by a coughing motion within the valve it self.
Of course the more plants you grow the more `Drip Linesí you will need, and the more expensive it will become to use them, but anyone with a modicum of DIY skills could install this simple answer to our water troubles. Once install a programmer on the tap will do the rest. Iíve looked at most types and eventually chose Hozelockís Aqua Control C4 which gives four programmes a day of anything up to an hour long, but as weíre not growing Watercress mine will be set at a fifteen minute duration four times a day. John Menzel assured me in Australia with their diabolical growing conditions, he waters for a very short time compared to using a hand held device. I for one believe him, and Iím completely sold on the whole idea. It seems to me if I give my charges only four applications the total water saved will be enormous, and of course supplying a good mulch and shade cloth will help the evaporation loss. The beauty of the idea is this, it puts moisture were the plant can use it at that particular time, and no more than eighteen inches down in that vital root area. As no water is applied to the foliage this to my mind could delay the appearance of downy mildew when conditions are rife, and while we are watering a liquid fertilizer in a weak state could be given to the plants if an in line feeder is present at some point before the moisture gets to the plants. In these unusual times when weather patterns are constantly changing anything that can make the growing of our beautiful flower easier should be grasped with both hands. So this is what I will be doing this year to get my seedlings to Shepton Mallet, and like all enthusiasts Iím refreshed and raring to go once more, but only time will tell if all this beats what our forefathers have been doing for centuries. Oh the title? I wanted to grab your attention thatís all.
See you at the trials.